SAE International revises AS33514 roughly every 5–7 years. The latest revision (as of 2025) is , which clarified torque values for titanium tubes and added requirements for laser-etched traceability.
SAE AS33514 is an aerospace standard that specifies the standard dimensions and requirements for flareless tube connection fitting ends and gasket seals. Overview of the Standard
The current version is AS33514E, published in 2019. Always check SAE International's website for the most up-to-date information.
If you're interested in exploring a related standard, such as (for external threads) or AS5863 (for female 24° cone connections), just let me know. sae-as33514
Legacy fittings (like MS33656 or AS4841) have served us well, but they share a common vulnerability: . In high-pressure hydraulic systems (3,000–5,000 psi), a single misaligned thread or under-torqued nut is a catastrophic failure waiting to happen.
Failure in any of these tests disqualifies a product from claiming compliance with SAE-AS33514.
SAE-AS33514 is frequently cited in broader military specifications (MIL-SPECS) for hydraulic and fuel systems: SAE International revises AS33514 roughly every 5–7 years
The standard covers tube outside diameters (OD) ranging from 3/16 inch up to 2 inches. Common sizes include:
Years ago, the design team had a choice: use old-fashioned "flared" fittings that required the ends of metal tubes to be widened like a bell, or go with the modern AS33514 flareless standard. They chose the latter because AS33514 fittings use a "bite-type" sleeve that grips the tube without requiring it to be flared, making the assembly lighter and more resistant to the constant vibrations of jet engines.
connections. Instead of widening the end of the tube, these fittings often use a "bite-type" sleeve or a gasket seal to create a leak-proof joint. saemobilus.sae.org Weight Savings: Overview of the Standard The current version is
While the full spec is technical (and behind SAE’s paywall), the core innovation revolves around and visual torque verification .
In the real world, SAE-AS33514 refers to the Aerospace Standard specification for shackles (specifically Safety Anchor Shackles). They are critical components used in lifting, towing, and tie-down operations in aviation and aerospace, designed to exacting standards of strength and reliability. In the story, the shackle acts as a symbol of reliability under extreme pressure.
The primary function of AS33514 is to provide a standardized interface for and gasket seals in aircraft fluid systems. Unlike traditional flared fittings that require the tube end to be mechanically spread, flareless fittings use a bite-type sleeve or a specific internal cone geometry to create a high-pressure seal. Key features of AS33514 include: